Various types of apparatus are used, for example, when substrates in film or layer form such as labels are to be coated over the surface thereof with liquid adhesive, such as hot melt adhesive. Usually the adhesive is kept in a fluid source which is heatable so that the adhesive can be kept in a fluid condition. That fluid source is connected to a main body of the apparatus by way of a hose connection. The fluid adhesive is conveyed by a conveyor means, such as a gear pump, through suitable bores into the apparatus and further conveyed through a distributor passage in the nozzle arrangement. The nozzle arrangement usually comprises two block portions. On the way to the distributor passage the adhesive passes through a passage portion into which a valve body of an application valve can engage so that the flow can be selectively enabled or interrupted. The distributor passage communicates with a nozzle opening or outlet opening from which the adhesive is applied to a substrate. That outlet opening can be in the form of an elongate slot as is known, for example, from DE 299 08 150. In that case the distributor passage communicates with the outlet opening by way of an elongate uninterrupted opening. The length of the operative portion of the outlet opening is set by a closure body which is arranged movably in the distributor passage.
A disadvantage with such apparatus is that the nozzle arrangements are usually of dimensions which do not allow the apparatus to be used for coating small components. In particular, the use of nozzle arrangements of such dimensions is ruled out when the coating has to be produced within a narrow opening. Such openings are usually to be found in honeycomb plate structures. In particular, sealing the nozzle arrangement, which often consists of two block portions, represents a problem.
Therefore the object of the present invention is to provide an apparatus which at least minimizes the above-mentioned disadvantages and which is suitable in particular for use in spatially constricted environments.